Add text and JSON formatters with real-time progress via traverser hooks,
summary statistics, and CLI integration for --show-* and --json flags.
Co-authored-by: multica-agent <github@multica.ai>
Add Resolver interface, BasicResolver, and CachingResolver to internal/dns.
CachingResolver wraps any Resolver with an in-memory cache keyed by
(server IP, name, type, class). Cache entries respect DNS TTL from
responses, falling back to a configurable default TTL. Thread-safe
using sync.RWMutex. Includes Len, Clear, and PurgeExpired methods
for cache management.
Closes HAN-379 (Phase 2.2).
Co-authored-by: multica-agent <github@multica.ai>
Add RootServer struct and DiscoverRoots function that queries the local
resolver for NS records of the root zone, resolves each root name to
A/AAAA addresses, and returns a list of RootServer structs.
Supports:
- Default: discovers a single root server from local resolver
- --root-server override to target a specific root server
- --all-root-servers to discover all 13 root servers
- --root-aaaa flag to include IPv6 addresses
Includes unit tests for all helper functions and integration tests
that skip gracefully when no resolver is available.
Co-authored-by: multica-agent <github@multica.ai>